Fig. 3. Effect of ECE on osteoclast-specific genes and transcriptional factor expression levels in RANKL-induced RAW 264.7 macrophages. TRAP: tartrate-resistant acid phosphatase, MMP-9: matrix metallopeptidase-9. Cells were incubated for 2 days in the presence of RANKL (50 ng/ml), M-CSF (25 ng/ml), and samples. (A) Osteoclast-specific genes (TRAP, cathepsin K and MMP-9) expression levels and (B) Osteoclast proliferation- related transcriptional factor (NFATc-1 and c-fos) expression levels were analyzed using qPCR and normalized to that of β-actin. Bars with different letters indicate significant differences at p <0.05.